Finding the Fourth Proportional to 138.49, 207.80 and 69.99
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Solution
The fourth proportional to 138.49, 207.80 and 69.99 is: 105.01
Step by Step Solution
- Step 1: Write the proportion equation
138.49 : 207.80 = 69.99 : x - Step 2: Convert to fraction form
138.49/207.80 = 69.99/x - Step 3: Cross multiply
138.49x = 207.80 × 69.99 - Step 4: Simplify right side
138.49x = 14,543.06 - Step 5: Solve for x
x = 14,543.06/138.49 - Step 6: Final answer
x = 105.01
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.